喷气织机辅助喷嘴流场特性与耗气量分析

为研究辅助喷嘴几何结构对喷嘴喷射效果及耗气量的影响,采用CFD软件Fluent对喷气织机辅助喷嘴流场进行数值模拟,获得了辅助喷嘴在不同供气压力、出口截面积、出口形状及喷射角下的纬纱飞行轴线气流速度分布。结果表明:随压力增大,射流速度的提升逐渐变弱,耗气量随压力呈正相关变化;喷嘴出口截面积影响射流速度和持续性,随截面积增加耗气量不断增大;截面积一定时,出口形状变化对筘槽内流场影响较小;纬纱飞行方向上气流速度及峰值位置随喷射角而变化,在实验范围内,喷射角越大耗气量越小,选择合适的辅助喷嘴和引纬工艺,是实现喷气织机高质低耗目标的关键。

Analysis on weft insertion flow field and gas consumption of auxiliary nozzle in air-jet loom

In order to study the influence of the auxiliary nozzle geometric structure on the nozzle jet effect and air consumption, the weft insertion flow field of the auxiliary nozzle was simulated with CFD software Fluent. The velocity distributions on the axis of weft flying of auxiliary nozzle under different conditions, such as the input air pressure, the outlet cross?sectional area, the outlet shape and the spray angle of auxiliary nozzle, are obtained. Results indicate that, with the increasing of input air pressure, the velocity of airflow is improved, while the increasing rate has been decreased. Gas consumption varies with the pressure positively. The velocity and sustainability of the air flow are determined by outlet cross?sectional area of auxiliary nozzle, and the air consumption is increasing with the growth of the cross?sectional area. For a given outlet cross?sectional area, various outlet shapes of auxiliary nozzle make little difference on the flow fields. Different nozzle spray angles correspond to different velocities and peak positions on the direction of weft flying, and the air consumption is reduced with the increasing of spray angle in the experimental range. Therefore, appropriate auxiliary nozzle and weft insertion process play a critical role of achieving high air?jet loom quality and low consumption.